Bleeding as a result of surgery or injury may be controlled by passive hemostats and/or hemostatic agents. Passive hemostats control bleeding mechanically, through pressure and absorption, and may be fragmented or otherwise mechanically disrupted powders, gauze, or sponges made from oxidized regenerated cellulose, or cross-linked gelatin. Often, a passive hemostat is combined with an active hemostat, such as thrombin. There remains a need, however, for improved hemostatic compositions, particularly those that render superior clot formation.